FILE - In this May 27, 2015 file photo Christoph Buehrer, left, director of neonatology at Charite Hospital and Wolfgang Henrich, director of gynecology at Charite Hospital, brief the media about the situation of 65-year old mother Annegret Raunigk and her quadruplets, in Berlin, Germany. Doctors said Wednesday, June 17, 2015 quadruplets born prematurely a month ago to a 65-year-old woman in Germany are doing well and gaining weight but one remains on a respirator. (AP Photo/Markus Schreiber, file)
(The Associated Press)

BERLIN – Doctors say quadruplets born prematurely a month ago to a 65-year-old woman in Germany are doing well and gaining weight but one remains on a respirator.

Berlin's Charite hospital said Wednesday the four babies — a girl named Neeta and three boys named Dries, Bence and Fjonn — have put on 30 to 50 percent of their birth weights since they were delivered by cesarean section on May 19.

The hospital says one has been taken off a respirator but another still needs help breathing.

Annegret Raunigk is believed to be the oldest woman to have ever delivered quadruplets.

The retired schoolteacher already has 13 other children aged 9 to 44 from five fathers. She traveled abroad to have donated, fertilized eggs implanted — a procedure that's illegal in Germany.